Technical Abstract:
The Agricultural Research Service of the United States Department of Agriculture announces the release of a novel featherless (scaleless) broiler line. Featherlessness in the scaleless lines is the result of an autosomal recessive gene that spontaneously arose in a commercial New Hampshire meat-type chicken strain and was first described by Abbott and Asmundson in 1957. The featherless condition results from the failure by the ectoderm to transcribe the genes for fibroblast growth factors FGF-2 and FGFR-1. These growth factors are necessary for formation of ectoderm derivatives, such as feathers, spurs, and scales. Dr. R. Jeffrey Buhr, Research Animal Physiologist at the USDA-ARS Richard B. Russell Agricultural Research Center in Athens, GA, has developed the featherless broiler line over the past five years. Stocks originating from scaleless low-line hatching eggs were obtained from the University of California-Davis in December 1999. At that time, body weight of scaleless line hens at 18 weeks of age averaged 1.3 kg and 1.5 kg for roosters. To obtain feathered and featherless broilers of comparable body weight at the time of processing (six weeks of age), roosters from this foundation line were mated via artificial insemination to a commercial strain of broiler breeder hens. Chicks from this mating were all feathered (heterozygous for the scaleless gene +/sc) and were raised to maturity. This feathered hybrid line was intermated and produced sibling chicks in an approximate ratio of three-fourths feathered and one-fourth featherless. From these chicks, featherless roosters selected for high body weight and large chest circumference were mated back to their parental hens to produce feathered and featherless chicks that were grown to maturity. Over the next two years, selected featherless rosters were mated to additional flocks of commercial broiler breeder hens. Currently feathered and featherless broilers obtain body weights comparable to commercial broilers at the time of processing, 2.2 kg at six weeks of age. The featherless broiler line has been used to document the lack of influence of empty feather follicles on the bacterial levels of both post defeathered and post immersion chilled carcass and the results have been published in Poultry Science. Fertile hatching eggs and chicks are available to researchers now in 2005.